To avoid confusion, remember PEMDAS. This is the order of operation.
Parenthesis, Exponents, Multiply, Divide, Add, Subtract
21 ÷ 7 + 20 * 102 * 2 - 3
No parenthesis and no exponents, proceed to multiplication.
20 * 102 * 2 = 4,080
Then, perform division
21÷7 = 3
Then, do addition
3 + 4080 = 4083
Lastly, do subtraction
4,083 - 3 = 4,080
So, 21 ÷ 7 + 20 * 102 * 2 - 3 = 4,080
THEREFORE THE ANSWER IS 4,080
The unknown number is - 2.5
Let the number = n
The equation will be formed as follows;
- eight times a number plus two = 8n + 2
- Two times the quantity of eight times a number plus two = 2(8n + 2)
- two times the same number minus seven = 2n - 7
- three the quantity of two times the same number minus seven = 3(2n-7)
Our final equation becomes;
2(8n + 2) = 3(2n-7)
Simplify as follow, to determine the unknown number;
16n + 4 = 6n - 21
16n - 6n = -25
10n = -25
n = -2.5
Thus, the unknown number is - 2.5
Learn more here: brainly.com/question/13818690
7. general term of gp is given by ar^n-1
hence,4th term is given by
ar^3=15 ------(1)
ar^6=405-----(2)
equation 2/1,we get
r^3=27
so common ratio r=3
putting value of r in equation 1,
we get a=5/9
so gp upto 7 terms will be 5/9,5/3,5,15,45,135,405
8. a=3
given 4th term is -24
so ar^3=-24
substituting value of a we get r^3=-8
r^3= -2^3
so r = -2
using this x2 is ar= 3*-2=-6
x3 is ar^2= 3*4=12
Answer:
Second choice.
Step-by-step explanation:
Option 1: solve the inequality. Add 7 to both sides, and multiply by -3 (don't forget that this makes the inequality switch direction!) to get 
or x > -9
Option 2. Plug 0 in it. You get -7 < 20, which is obviously true. So 0 is in the set of solution and it means B and C are possible solutions. So let's check another easy value. let's say -10. replacing it you get 
or 
. But 23 is obviously greater than 20, which means -10 is not a part of the solution. Correct answer is B
